Proximity Ligation Assay of GluN1 and D1R

Brain slices were prepared as previously described^{21 (link)} and proximity ligation assay (PLA) was performed using the Duolink in situ kit (Olink Bioscience, Uppsala, Sweden) according to the manufacturer's instructions with the following modifications: PLA probes incubation was for 2 h; ligation was performed for 45 min; amplification step was extended for 2 h with a concentration of polymerase of 1/60 all at 37°C. Striatal primary cultured cells were plated into 8-μ well plates (LabTek, Dutscher, Brumath, France). Blocking (1 h at room temperature) and primary antibody (overnight at 4 °C) incubations were performed in a 3% bovine serum albumin (Sigma Aldrich) and 0.2% Triton X-100 solution. Rabbit anti-GluN1 (ab17345, Abcam, Cambridge, MA, USA) and rat anti-D1R (D2944, Sigma Aldrich) were diluted (1:500) in the blocking solution. The anti-rabbit (+) PLA probe (1:5) along with an anti-rat (−) probe (1:100) were diluted in the blocking solution. Anti-rat PLA probes were generated according to the manufacturer's instructions using the Duolink Probemaker (Olink Bioscience). Goat-anti-rat IgGs (Santa Cruz, Heidelberg, Germany) were used. Cells were mounted in FluorSave (Calbiochem). Image acquisition and quantification are detailed in the Supplementary Information section.